Bipolar CMOS DMOS (BCD) process technology enables incorporation of analog components, digital components and high voltage (HV) devices into a single chip or integrated circuit (IC) to form an embedded device. Such chip or IC is widely used in automotive and industrial applications. Nevertheless, it is difficult to integrate these different types of devices in a single die or chip since interference is prone to occur between the different devices. For example, high voltage devices may have latch up problem. This may undesirably affect the reliability of the overall product during integration. As such, there is a need to properly isolate the different types of devices from each other during integration. However, conventional junction isolation technique used for isolating the different types of devices consume larger layout area and require additional masking steps which may complicate the manufacturing process and increases the manufacturing cost. Moreover, the HV devices integrated with analog and digital components using conventional isolation scheme for isolation may not have the desired high breakdown voltage (BV) for high performance.
From the foregoing discussion, it is desirable to provide a reliable, high performing, simplified and cost effective solution to integrate various suitable isolation structures to effectively isolate HV devices from other devices in the same IC.